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iOS Build a Weather App with Swift Managing Complexity Callback Methods With Closures

Pascal Brisset
Pascal Brisset
2,290 Points
Posted by Pascal Brisset
Pascal Brisset
2,290 Points

Preview is blank for this fetchTreehouseBlogPosts challenge

I can't seem to understand what is wrong with my code :(

Callbacks.swift 
import Foundation

// Add your code below

func fetchTreehouseBlogPosts(result: NSData!, request: NSURLResponse!, error: NSError! -> Void) {

}
Roberta Voulon
Roberta Voulon
5,792 Points
Roberta Voulon
Roberta Voulon
5,792 Points

I think a ton of people are stuck on this, I finally got a hint from somewhere and it worked for me, so I'm re-posting this where I can: What made it work for me in the end was wrap the signature in outer parenthesis like this:

typealias BlogPostCompletion = ((NSData!, NSURLResponse!, NSError!) -> Void)
func fetchTreehouseBlogPosts(completion: BlogPostCompletion) {}

You shouldn't have to do this though! It's perfectly valid without the wrapping parentheses.